Side rail extrusion for a window



FIG. 1 is a front elevational view of a side rail extrusion for a window showing my new design;

FIG. 2 is a right side elevational view thereof;

FIG. 3 is a rear elevational view thereof;

FIG. 4 is a left side elevational view thereof; and,

FIG. 5 is a top plan view thereof. 

The ornamental design for a side rail extrusion for a window, as shown and described. 